Characteristics and soil nutrient dynamics in beginning period of artificial vegetation on rock slope

In order to understand the vegetation characteristics and nutrient variation in the beginning period of ecological protection engineering on the rock slope, taking an actual project as study case, the location study method was adopted to investigate the main community characteristics such as species composition, coverage and height, and soil nutrient factors such as organic matter and available nutrient elements on three slopes with different aspect and gradient in the first year after vegetation planted. Results showed that: 1) During the first year since artificial vegetation planted, there was significant seasonal changes on quantitative characteristics of plant communities. The number of species was more in the beginning period, then reached the minimum in the winter and spring, while gradually increasing after returning green in the second year. On the three slopes, the average coverage of live parts declined to the minimum in the winter and spring, and increased suddenly with the temperature increasing in May. After a year of planting, the average coverage was similar to each other with a value of about 60%. The average height of live parts of the vegetation changed with time and the variation was accorded to cubic power function. 2) The changing tendency of soil available nutrients and organic matter were similar in the three slopes during the first year. But there were obvious differences between each other. Content of available nitrogen and phosphorus decreased in the end of year, but the available nitrogen and organic matter increased. 3) By the multiple stepwise regression analysis, excluding organic matters of three slopes, other soil available elements showed multiple linear relationship with vegetation community characteristics. While the same soil nutrient factor and the matched indicator of vegetation community characteristics varied greatly among different slopes and they could not form a unified equation of interpretation. So more influence factors and interactive relationships should be considered synthetically in the follow-up studies.